The present invention is generally directed to toner and developer compositions, and more specifically the present invention is directed to imaging and printing processes with toner compositions, including magnetic single component liquid developers, and two component developer compositions containing polysilylenes. In one embodiment of the present invention there are provided toner compositions comprised of a polysilylene, a poly(germane), or mixtures thereof, and pigment particles. More specifically, in one embodiment the present invention is directed to low melting toner composition comprised of a polysilylene, pigment, or dye particles, and optional additive particles. Also encompassed by the present invention are developer compositions comprised of the aforementioned toner and carrier components. Examples of advantages associated with the toner compositions of the present invention include a lower minimum fixing temperature than many currently known toners, for example 125.degree. C., thereby permitting decreased power consumption and increasing the fuser roll life present in electrophotographic imaging processes; and nonblocking at temperatures of between about 118.degree. C. and less than about 140.degree. C., and specifically nonblocking at temperatures of from about 48.degree. C. to about 55.degree. C. There is also provided in accordance with the present invention imaging processes with positively or negatively charged toner compositions comprised of polysilylene resin particles, pigment particles, and charge enhancing additives. In addition, the present invention is directed to imaging processes with developer compositions comprised of the aforementioned toners, and carrier particles. Further, the processes of the present invention with the toner and developer compositions illustrated, including single component toners, enable reliable output copy quality and stable triboelectric charging properties for the toner compositions selected. Also, the present invention relates to liquid toner and developer compositions comprised of the polysilylenes, poly(germanes) or mixtures thereof illustrated herein; vehicles such as known Isopars, including Isopar G; and charge directors, reference U.S. Pat. No. 3,850,829, the disclosure of which is totally incorporated herein by reference.
Many toner and developer compositions are known. For example, toner compositions with styrene acrylates, styrene methacrylates, polyesters, styrene butadienes, and the like are illustrated in the prior art. Also, toners with additives including charge enhancing components, metal salts, metal salts of fatty acids, colloidal silica, and the like are known. Further, developer and toner compositions with certain waxes therein are known. For example, there are disclosed in U.K. Patent Publication 1,442,835, the disclosure of which is totally incorporated herein by reference, toner compositions containing resin particles, and polyalkylene compounds, such as polyethylene and polypropylene of a molecular weight of from about 1,500 to 6,000, reference page 3, lines 97 to 119, which compositions prevent toner offsetting in electrostatic imaging processes. Additionally, the '835 publication discloses the addition of paraffin waxes together with, or without a metal salt of a fatty acid, reference page 2, lines 55 to 58. In addition, many patents disclose the use of metal salts of fatty acids for incorporation into toner compositions, such as U.S. Pat. No. 3,655,374, the disclosure of which is totally incorporated herein by reference. Also, it is known that the aforementioned toner compositions with metal salts of fatty acids can be selected for electrostatic imaging methods wherein blade cleaning of the photoreceptor is accomplished, reference U.S. Pat. No. 3,635,704, the disclosure of which is totally incorporated herein by reference. Additionally, there are illustrated in U.S. Pat. No. 3,983,045 three component developer compositions comprising toner particles, a friction reducing material, and a finely divided nonsmearable abrasive material, reference column 4, beginning at line 31. Examples of friction reducing materials include saturated or unsaturated, substituted or unsubstituted, fatty acids preferably of from 8 to 35 carbon atoms, or metal salts of such fatty acids; fatty alcohols corresponding to said acids; mono and polyhydric alcohol esters of said acids and corresponding amides; polyethylene glycols and methoxy-polyethylene glycols; terephthalic acids; and the like, reference column 7, lines 13 to 43.
Described in U.S. Pat. No. 4,367,275 are methods of preventing offsetting of electrostatic images of the toner composition to the fuser roll, which toner subsequently offsets to supporting substrates such as papers wherein there are selected toner compositions containing specific external lubricants including various waxes, see column 5, lines 32 to 45.
Other references of interest which disclose, for example, the use of amides as toner additives include U.S. Pat. No. 4,072,521; 4,073,649 and 4,076,641. Furthermore, references of background interest are U.S. Pat. Nos. 3,165,420; 3,236,776; 4,145,300; 4,271,249; 4,556,624; 4,557,991 and 4,604,338.
Moreover, toner compositions with charge enhancing additives are known including, for example, distearyl dimethyl ammonium methyl sulfate, reference U.S. Pat. No. 4,560,635, the disclosure of which is totally incorporated herein by reference. As preferred carrier components for the aforementioned compositions, there are selected steel or ferite materials, particularly with a polymeric coating thereover, including the coatings as illustrated in U.S. Ser. No. 751,922, entitled Developer Composition with Specific Carrier Particles, the disclosure of which is totally incorporated herein by reference. A particularly preferred coating illustrated in the aforementioned copending application is comprised of a copolymer of vinyl chloride and trifluorochloroethylene with conductive substances dispersed in the polymeric coating inclusive of, for example, carbon black. One embodiment disclosed in the aforementioned copending application is a developer composition comprised of styrene butadiene copolymer resin particles, and charge enhancing additives selected from the group consisting of alkyl pyridinium halides, ammonium sulfates, and organic sulfate or sulfonate compositions; and carrier particles comprised of a core with a coating of vinyl copolymers, or vinyl homopolymers. The polymeric components of the aforesaid copending application are also selected for various embodiments of the present invention as illustrated herein. Additionally, there is described in the U.S. Pat. No. 3,893,935 the use of certain quaternary ammonium salts as charge control agents for electrostatic toner compositions. There is also described in U.S. Pat. No. 2,986,521 reversal developer compositions comprised of toner resin particles coated with finely divided colloidal silica. According to the disclosure of this patent, the development of images on negatively charged surfaces is accomplished by applying a developer composition having a positively charged triboelectric relationship with respect to the colloidal silica. Further, there is illustrated in U.S. Pat. No. 4,338,390, the disclosure of which is totally incorporated herein by reference, developer and toner compositions having incorporated therein as charge enhancing additives organic sulfate and sulfonate compositions; and in U.S. Pat. No. 4,298,672, the disclosure of which is totally incorporated herein by reference, positively charged toner compositions containing resin particles and pigment particles, and as a charge enhancing additive alkyl pyridinium compounds, inclusive of cetyl pyridinium chloride.
Other prior art disclosing positively charged toner compositions with charge enhancing additives include U.S. Pat. Nos. 3,944,493; 4,007,293; 4,079,014 and 4,394,430.
There were located as a result of a patentability search U.S. Pat. Nos. 3,850,829; 4,430,408 and 4,770,968. In the '829 patent there are illustrated liquid developers comprised of an organosol portion, reference the Abstract of the Disclosure, and particularly the organosol as illustrated in columns 3 and 4. Note Example A wherein there is formulated an organosol part by mixing 250 grams of silicon resin with 250 grams of Isopar G, and wherein the silicon resin is an organopolysiloxane of the formula as illustrated in column 3, line 60. The '408 patent describes developer powders containing a fluorene modified alkyl siloxane and a surface treatment of carbon black, reference the Abstract of the Disclosure. The '968 patent illustrates polysilane styrene butadiene terpolymers and the use thereof in toner and developer compositions.
Although the above described toner and developer compositions are useful for their intended purposes, there is a need for improved compositions. More specifically, there is a need for toner compositions wherein other polymer resins are selected. There is also a need for low melting toner compositions with the advantages illustrated herein. Further, there is a need for toner resins comprised of polysilylenes, or polyorganosilanes, poly(germanes), or mixtures thereof. In addition, there is a need for toner compositions wherein the amount of power needed for the melting thereof is decreased from, for example, about 10 to about 25 percent, and wherein fuser roll life is increased as indicated herein. There is also a need for developer compositions comprised of the toner compositions illustrated herein and carrier components. The toner and developer compositions of the present invention can be selected for electrophotographic imaging and printing processes, especially xerographic processes as illustrated, for example, in many of the U.S. patents mentioned herein. Also, the polysilylenes and the other referenced toner resin components of the present invention may be selected as carrier coatings, or as coatings for fuser rolls.
Furthermore, the polysilylenes, poly(germanes), or mixtures thereof may be selected as resin components for liquid toner compositions containing, for example, petroleum distillates such as the known Isopars and a charge director such as barium petronate, lecithin, and the like, which charge directors are usually present in an amount of from about 0.1 to about 15 weight percent. Moreover, there is a need for toner compositions containing a polysilylene or a poly(germane) with glass transition temperatures of from about 50.degree. to about 60.degree. C., and with melting temperatures of from between about 50.degree. C. to about 120.degree. C. in some embodiments.